Beijing on Saturday voiced its anger over a meeting between Mexican President Felipe Calderon and the Dalai Lama.
"This grossly interferes in China's internal affairs, and hurts the feelings of the Chinese people," Chinese foreign ministry spokesman Ma Zhaoxu said in a statement.
In line with normal practice, the foreign ministry and the Chinese ambassador to Mexico have made a formal complaint over the meeting.
During the private talks however, the Mexican leader reiterated his country's adherence to the "one-China principle" and its recognition of China's full sovereignty over Tibet.
Beijing regards Tibet as an "inseparable" part of China and the Dalai Lama -- who lives in exile in India -- as a "splittist" bent on dividing the country. It regularly protests over his meetings overseas.
In July, China said US President Barack Obama's talks with the Buddhist monk had damaged relations between the two countries.
The Dalai Lama says he is peacefully seeking greater rights in Tibet and accepts Chinese rule.
The Nobel Peace Prize winner fled Tibet following a failed uprising against Chinese rule in 1959. He later founded Tibet's government in exile in Dharamshala, northern India, but gave up his political leadership role in May.